Read csv files by regulare expression function

Hi,

I have multiple .csv files in the following format from:

TRMM_1998_01_newntcl.csv
TRMM_1998_02_newntcl.csv
.
.
.
TRMM_1998_12_newntcl.csv
TRMM_1999_01_newntcl.csv
.
.
.
TRMM_1999_12_newntcl.csv

I have the following code and I need to modify to read by month (1-12). I appreciate if someone can help me to figure this out and modify the following code.

Thanks in advance.

      sad = dir('TRMM_*_newntcl.csv');
      cac = regexp( {sad.name}, '1998_[01]\d_[0-3]\_' ); 
      ism = not( cellfun( @isempty, cac ) );
      d   = sad(ism);
      ymdh=cell2mat(textscan([d.name], ...
              'TRMM_%4d_%2d_%2d%2d_newntcl.csv', ...
              'collectoutput',true));

Answer 1

[Walter Roberson]

month_to_match = 8;  %for example
str_for_month = sprintf('%02d', month_to_match);
regexp_for_month = [ '^TRMM_[12]\d{3}_[01]\d_' str_for_month '_'];
cac = regexp( {sad.name}, regexp_for_month );

[Damith]

This part

'^TRMM_[12]\d{3}_[01]\d_'

in the following line does not read as TRMM_year_ but 'str_for_month' displaying correct month 08 in the above example. Therefore, it reads all the files.

I have 48 csv files starting from TRMM_1998_01_newntcl.csv to TRMM_2001_12_newntcl.csv.

regexp_for_month = [ '^TRMM_[12]\d{3}_[01]\d_' str_for_month '_']; This line does not work.

[Walter Roberson]

regexp_for_month = [ '^TRMM_[12]\d{3}_' str_for_month '_'];

[Damith]

OK. Thanks. This worked.

Answer 2

[Stephen23]

You could avoid the whole regexp thing entirely by using my FEX submission datenum8601:

>> N = cellfun(@datenum8601, strrep({sad.name},'_','-'));
>> datevec(N)
ans =
      1998           1           1           0           0           0
      1998           2           1           0           0           0
      1998          12           1           0           0           0
      1999           1           1           0           0           0
      1999          12           1           0           0           0

[Damith]

Thanks Stephen.But, I need to somehow use to above approach with regexp function.